1. Field of the Invention
This invention relates to computer input devices and, more particularly, to a deformable cap for a computer pointing device.
2. Description of the Relevant Art
Modern computer systems that implement graphical user interfaces (“GUIs”) typically include one or more pointing devices for the computer operator. Pointing devices typically allow an operator to move a cursor about the computer screen and to select objects. A commonly used pointing device is the computer mouse. Operation of the computer mouse typically requires a relatively large flat space. A variety of other pointing devices have been developed in an attempt to reduce the area occupied by the pointing device or required for use by the pointing device. A pervasive trend with notebook-style portable computers (also referred to as laptop computers) is attempting to reduce the size of every component of the computer while maintaining ease of use for the operator. Development of new pointing devices is, therefore, particularly important for portable computers. For instance, the computer mouse is difficult to use when not sitting at a desk. Additionally, pointing devices that utilize less area may be mounted directly on the portable computer.
One type of alternative computer pointing device is a miniature joystick-type pointing device that is often mounted within a keyboard. An example of a miniature joystick-type pointing device is the TrackPoint™ manufactured by the IBM Corporation of Armonk, N.Y. The TrackPoint™ includes a control stick placed within a keyboard, typically between the “G”, “H”, and “B” keys. The keyboard may be that of either a portable computer or a desktop computer. The top of the control stick is typically covered by a cap with a high-friction fuzzy surface. An operator applies a force to the control stick using a single finger. The bottom of the control stick is coupled to a sensor that detects any movement of the control stick. The sensor is located within the keyboard. The output of the sensor is typically adapted such that a force applied by an operator in a given direction on the control stick results in movement of a cursor on a computer monitor in the corresponding direction.
A similar miniature joystick-type pointing device is the ScrollPoint™ also manufactured by the IBM Corporation of Armonk, N.Y. The ScrollPoint™ includes a control stick covered by a cap of a high-friction fuzzy material and is mounted on a computer mouse between the two mouse buttons. The control stick is coupled to a sensor located within the computer mouse. An operator applies a force to the control stick using a fingertip and the direction of the force is detected by the sensor. The output of the sensor is typically adapted to control scroll bars located on a computer monitor.
Although miniature joystick-type pointing devices, such as the TrackPoint™ and ScrollPoint™, occupy a minimal amount of space and provide an intuitive interface for an operator to control a cursor or a scroll bar, utilization of the devices by an operator may sometimes prove difficult. Since the devices are made small enough to comfortably fit on a keyboard or mouse, the surface area of contact between the operator's finger and the cap of the control stick is small. Additionally, both the cap and the operator's finger have convex shapes that further reduce the contact surface area.
Although the cap placed on the control stick may be made of a high-friction fuzzy surface (i.e., a surface with a plurality of short fiber adhered to it outer surface), the operator may still be required to exert a relatively large force to keep his/her finger from slipping off the cap. First time users may experience difficulty exerting the correct force to keep their fingers from slipping. Additionally, after extended use of the pointing device, an operator may experience pain and soreness in his/her fingertip.
The high-friction fuzzy surface of the cap may become smooth after use thereby necessitating frequent replacement. As the surface of the cap becomes smooth, an operator will be required to exert even greater force to keep his/her finger from slipping. If the cap is not replaced once it becomes smooth, the operator may experience increased levels of discomfort in his/her fingertip.
It is therefore desired to develop an improvement to the miniature joystick-type pointing device that increases the comfort level of the operator using the device. New operators of the pointing device should be able to easily adapt to utilization of the device. Additionally, long-term use of the pointing device should not cause the operator to experience discomfort in his/her finger. It is also desired that the improvement may work with both new pointing devices and existing pointing devices already in use such as the TrackPoint™ and ScrollPoint™.